The present invention relates to a cassette storage container made of a plastic resin sheet material.
There has been proposed a cassette storage container made of a cardboard material in the form as shown in FIG. 1 for containing a video tape cassette 100 as shown in FIG. 2, wherein a case body 1 is provided with a transparent window 30 for visually displaying a label 25 attached on one surface of the video tape cassette 100 when the cassette 100 is accommodated in the case body 1. In the conventional cassette storage container, the window 30 is formed by defining an opening 31 on the corresponding face of the case body 1 with a transparent sheet 32 fitted on the inner surface of the case body 1 so as to cover the opening 31. Apparently, for manufacturing the conventional cassette storage containers, two members i.e., the case body and the transparent sheet for the window are necessary and furthermore, since the transparent sheet 32 must be adhered on the case body, the manufacturing process is complicated, thereby making the manufacturing cost to be expensive.
In order to eliminate the drawbacks as described above, there has been proposed making the cassette storage container of one transparent plastic resin sheet. However, when a plurality of the transparent plastic resin sheets are stacked, they tend to fit or stick to each other. Therefore, in the manufacturing of the cassette storage containers using such transparent plastic resin sheets in attempting to take the lowest sheet from the stacked sheets one by one, two or more sheets undesirably are removed from the stacked sheets at a time. In such a case each of the fitted sheets must be manually separated, thereby lowering productivity of the cassette storage containers. Furthermore, scratches may easily occur on the transparent sheets when separating the fitted sheets whereby the appearance of the containers may be harmed.
In order to eliminate these drawbacks it has been further proposed to make the cassette storage containers using sheet materials having rough surfaces. In this case, however, since the transparency of the case body is not sufficient, the contents of the label on the video tape cassette accommodated in the cassette storage container may not be clearly seen through the window.